[Nix-dev] Re: FOSDEM 2008 meeting

[Ludovic Courtès]

Hi!

Eelco Dolstra <e.dolstra at tudelft.nl>
writes:

> It has gotten a lot slower over the last few months: it used to take 2
> or 3 seconds (provided that all the Nix expressions where in the disk
> cache - all the seek times for those small files add up), but now it's
> more like 10.  This is probably because some expensive computations
> are being done in Nix expressions (like the uniqList function) which
> might be done in a different way or turned into primops.

I see.

> So we should do some profiling...

Should we also have a profiler for the Nix language itself?  ;-)

> Yes, exactly.  nix-env -i has to look at all packages to evaluate the
> name attribute, while nix-env -i -A (= nix-build) only evaluates what
> is necessary. nix-env -i -A also has the advantage that it's
> unambiguous wrt which package to install, so maybe we should make it
> the primary user interface ;-)

I think you're jumping to the conclusion.  ;-)

The bad news is that is would be even harder to provide functionality
similar to "apt-cache search" (e.g., search for regexp matches in
`meta.description').

Thanks,
Ludovic.